Analyzing properties from black hole-neutron star merger outflows and modeling r-process nucleosynthesis

The LIGO and Virgo observatories have made over 35 gravitational wave detections thus far. Most of the signals detected have been confidently identified as either black-hole binaries, neutron-star binaries, or black hole-neutron star binaries. Near the time of merger, the only known way to solve Einstein’s equations to model these strongly gravitating systems is to use numerical relativity because then all pencil-and-paper approximations fail. Using the SXS Collaborations’ numerical relativity code, the Spectral Einstein Code (SpEC), I completed a hydrodynamic black hole-neutron star merger simulation to test and model the creation of heavy elements in a process called r-process nucleosynthesis to estimate the outflows of the merger. Investigating the ejected matter from BHNS mergers has been done before; however, for this project, we explored how r-process heating affects our estimations of how much matter is ejected from the merger.